Clustered Dock

Rumex conglomeratus Murray

Family: Polygonaceae.

Names:

Rumex is derived from the Latin name for Sorrel.
Conglomeratus is from the Latin con meaning to join and glomerus meaning to form into a ball and refers to the ball like clusters of fruit.
Clustered Dock refers to the clustered flowers on the stem and its membership of the Dock genus. Dock is from the Old English docce meaning a coarse weedy herb.

Other names:

Sharp Dock

Summary:

An erect stemmed plant with flat, crisped edge leaves on long stalks in a basal rosette and a leafy, branched stems with fruits in rings around the stem. The fruit has smooth wings with 3 swollen warts or tubercles. It has a perennial carrot like rootstock with annual top growth and flowers from October to December or occasionally in February.

Description:

Cotyledons:

Two. The cotyledon is 6 to 10 mm long with a petiole of approximately the same length, and is hairless. The seedling has a short hypocotyl and no epicotyl.

First Leaves:

The leaves develop singly, the first having a blade 10 to 20 mm long. Tip rounded. Sides convex. Base squarish. Petiole about the same length as the blade.

Leaves:

Develop a basal rosette with alternate stem leaves.
As the plant develops the leaves become more elongated and more pointed and have a base angle of less than 90 degrees.
Stipules - Ochrea, membranous sheath, to 40 mm long, translucent, at the base of the petiole.
Petiole - Slender.
Blade - Oblong to narrowly egg shaped, to 30-130 mm long x 10-40 mm wide, flat, dark green, wavy (crisped) edges, notched or right angled base, obtuse tip. Hairless.
Stem leaves - Alternate. Petiolate, some 30 to 50 mm long with those towards the top of the stem being shorter, with shorter petioles and more pointed tips. Hairless.

Stems:

Erect, stiff, fluted in cross section, 300-1500 mm tall, brownish green, sparsely branched, sometimes zig zag. The larger stems are hollow and the smaller solid with a pithy core. Stiff branches that bend upwards. Hairless.

Flower head:

A loose, open, narrow panicle composed of well separated, ring like, many flowered clusters that have a small petiolate leaf below (in some specimens the upper clusters don't have a leaf below). Formed on the upper parts of branches that are leafier towards the bottom.

Flowers:

Red-green on short stalks(pedicels).
Bracts - Ochreola, 1 mm long, translucent.
Ovary - 3 styles with large, tufted stigmas.
Perianth - 6 segments, 3 inner ones enlarged and close over the fruit.
Stamens - 6.
Anthers -

Fruit:

Firm textured achene comprised of a nut enclosed by 3 inner perianth segments or valves. Valves 2-3.5 mm long x 1-2 mm wide, smooth edged, oblong to narrowly egg shaped, smooth edged, obtuse tipped, usually with a large oblong tubercle that is sometimes almost as big as the valve. Achene on a 2-3 mm long, usually curved, stalk (pedicel) that holds it away from the stem. Red-brown when mature.

Seeds:

Dark brown, triangular pyramid nut, 1-1.5 mm long x 0.5 mm wide.

Roots:

Thick, carrot like rootstock that often branches.

Key Characters:

Perennial.
Leaf base cordate or truncate, not lobed.
Fruiting perianth inconspicuous.
Flowers bisexual, rarely polygamous.
Fruiting valves entire, tuberculate, oblong, 2-3.5 x 1-2 mm.
Panicle loose.
Adapted from J.M. Black, N.T. Burbidge and G. Perry.

Biology:

Life cycle:

Annual top, perennial rootstock. Seeds germinate and rootstocks form shoots in the autumn and produce a rosette of leaves in winter. Flowering stems emerge in spring to produce seed by early summer. The top growth normally dies off over summer.

Physiology:

Reproduction:

By seed and perennial rootstock.

Flowering times:

Spring in western NSW.
October to December in SA.
October to December and occasionally in February in Perth.

Seed Biology and Germination:

Exposure to light, alternating temperatures, stratification (chilling of moist seed) and nitrate increases germination.
Some seed is dormant.
Some seed may last for many years in the soil.

Vegetative Propagules:

Perennial rootstock.

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Seeds are spread mainly by animals, water and as contaminants of grain or hay.

Origin and History:

Europe. Central and south west Asia. Cosmopolitan.

Distribution:

ACT, NSW, QLD, SA, TAS, VIC, WA.
Wide spread and locally common in most parts of Tasmania.

Courtesy Australia's Virtual Herbarium.

Habitats:

Not as restricted to damp situations as some of the other Dock species.
Often in cooler mountain valleys at low elevations.

Climate:

Temperate. Mediterranean.

Soil:

Clays and fertile loams.

Plant Associations:

Many.

Significance:

Beneficial:

Detrimental:

Weed of roadsides, vegetables, pastures, streams, drains, wetlands and disturbed areas. Moderately competitive in pasture situations.

Toxicity:

May cause oxalate poisoning in stock.

Symptoms:

Oxalate poisoning.

Treatment:

Oxalate poisoning.

Legislation:

Noxious weed of WA.

Management and Control:

Seedlings less than 6 weeks old can usually be controlled by cultivation. Repeated cultivations over summer are required to control rootstocks.
Mowing and slashing are ineffective.
Some selective control in legume based pastures can be achieved by using glyphosate in a blanket wiper in late spring.

Thresholds:

Eradication strategies:

Remove isolated plants by cutting their roots at least 200 mm below ground level.
Apply 800 mL/ha glyphosate(450g/L) plus 40 g/ha Logran® plus 5 g/ha Ally® plus 1 L of Pulse® Penetrant per 400 L of spray mix, 2-3 weeks after the break. Cultivate 5 days later and plant wheat.
OR Apply 1000 mL/ha glyphosate(450g/L) plus 500 mL/ha Dicamba(200g/L) plus 1 L of Pulse® Penetrant per 400 L of spray mix, 2-3 weeks after the break and cultivate 5 days later and plant oats or barley.
6-8 weeks after planting apply 5 g/ha of Ally® in wheat and barley crops or 750 mL/ha of dicamba amine in oat crops.
In following break crops use triazine or urea herbicides to reduce the establishment of Dock for dormant seed.
In following clover pastures, Spray Graze with 750 mL/ha of 2,4-D amine(500g/L) 6-8 weeks after the break of the season to prevent seedlings establishing. Repeat this annually for at least 5 years.
In bushland, individual plants may be wiped with a mixture of 1 L glyphosate(450g/L) in 2 L water. Small infestations may be sprayed with 0.5g chlorsulfuron(600g/kg) plus 100 mL Tordon® 75-D in 10 L of water in winter. This mix controls existing plants and has residual activity to control seedlings for about a year. Some seed will remain viable in the soil for 20 years.
Blanket wiping with 1 L glyphosate(450g/L) plus 20 g chlorsulfuron(750g/kg) plus 2 L water in spring is reasonably selective in pastures. This mix may be applied manually to individual plants.
2 L/ha glyphosate(450g/L) can be used selectively in some seasons when dock is green in autumn or summer and the annuals are not. Metsulfuron is also effective. Grazing, mowing and cultivation usually lead to greater stands. Plant tall growing perennial species to increase the levels of shade and help reduce re-invasion.

Herbicide resistance:

Biological Control:

Related plants:

Bladder Dock (Rumex vesicarius now Acetosa vesicaria)
Broadleaf Dock (Rumex obtusifolius)
Curled Dock (Rumex crispus) is a tall plant up to 1.5 m tall with pointed oval leaves that are 4-24 cm long. The leafless inflorescence has densely clustered flowers and fruits. The fruit valves are reddish brown, swollen in the centre, with smooth margins and lacking teeth.
Fiddle Dock (Rumex pulcher) is a plant to 50 cm tall with rounded oblong leaves, the basal ones sometimes slightly constricted in the middle and appearing fiddle-shaped. The leaves are 4-15 cm long. The leafy inflorescence has distant whorls of flowers and fruits. The fruit valves are brown, swollen and warty in the centre and the margin has prominent stiff teeth.
Mud Dock (Rumex bidens)
Rambling Dock (Rumex sagittatus now Acetosa sagittata)
Shiny Dock (Rumex crystallinus)
Sorrel (Rumex acetosella now Acetosella vulgaris) has arrow shaped leaves.
Swamp Dock (Rumex brownii)
Wiry Dock (Rumex dumosus)

Plants of similar appearance:

Spiny Emex (Emex australis) looks similar especially when young.

References:

Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P208. Diagram of seed. Photo.

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P281. Diagram of seed.

Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P153, 155. Diagram of seed.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P234. Photo.

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney). P583.

Gilbey, D. (1989). Identification of weeds in cereal and legume crops. Bulletin 4107. (Western Australian Department of Agriculture , Perth). P24-25. Diagram of seed.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P200. Diagram of seed.

Hyde-Wyatt, B.H. and Morris, D.I. (1975). Tasmanian weed handbook. (Tasmanian Department of Agriculture, Hobart, Tasmania). P58-59. Diagrams.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #1072.4.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P116.

Parsons, W.T. and Cuthbertson, E.G. (1992). Noxious weeds of Australia. (Inkata Press, Melbourne). P552-554. Photos.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.